A known fuel injector (German Patent Application No. DE 197 44 739) has a housing assembled from multiple parts, of which one part is formed by an inlet stub having a fuel feed and one part is formed by a sleeve which is stepped in diameter. The tubular inlet stub plunges into the larger-diameter sleeve section of the sleeve and partially into the smaller-diameter sleeve section of the sleeve and carries, on its plunging end, a solenoid coil of an electromagnet which drives a valve needle, whose armature, which is fixedly connected to the valve needle, is guided axially displaceable in the end of the inlet stub plunging into the smaller-diameter sleeve section. The open end of the smaller-diameter sleeve section is closed by a valve body, on which a valve seat which surrounds a valve opening is formed. A closing head formed on the end of the valve needle interacts with the valve seat to release and close the valve opening. A perforated injection disc is situated downstream from the valve body. The area of the inlet stub protruding from the sleeve is enclosed by a plastic extrusion coating, which covers the opening of the larger-diameter sleeve section of the sleeve and ends at a distance from the intake-side end of the inlet stub. A connection plug for a solenoid coil of the electromagnet is embedded in the plastic extrusion coating. The fuel injector is inserted into a valve receptacle in the cylinder head of an internal combustion engine and sealed against the wall of the valve receptacle using two sealing rings. A lower sealing ring is accommodated in a ring groove provided on the ejection-side, lower end of the smaller-diameter sleeve section of the sleeve and an upper sealing ring is pushed onto the intake-side upper end of the inlet stub, which protrudes from the plastic extrusion coating. After installation of the injector in the valve receptacle, the upper sealing ring presses against the ring-shaped front face of the plastic extrusion coating.